Claudia Mo, a pro-democratic member of the Hong Kong Legislative Council, called on the Australian government to join mounting international opposition to the law, which would allow the territory to extradite criminals to the mainland.

"The Australian government must announce its stance on this very unacceptable law as soon as possible," she said.

"The European Union of 28 countries have done it. America, Canada have made it all very clear.

"It's about time Australia joined the international community in condemning this very evil law in Hong Kong."

The bill has drawn widespread criticism among the public and business community, who fear the law may be used to target critics of Beijing.

Opponents, including Ms Mo, also argue there is no guarantee of a fair trial or human rights for fugitives sent across the border.

The Australian Department of Foreign Affairs and Trade said the government was monitoring the situation, but would not move to oppose it.

"The Australian Government is taking a close interest in the proposed amendments to the Fugitive Offenders Ordinance in Hong Kong, including to ascertain any impacts on Australian residents," a spokesperson said on Friday.

"The Australian Consul-General in Hong Kong has raised the issue with senior levels of the Hong Kong government."

Under the 1997 handover from Britain to China, Hong Kong was promised autonomy and civic freedoms under the "one country, two systems" principle.

The UK and Canadian foreign ministers said this week it was important extradition arrangements were in line with that agreement.

"We believe there is a risk that the proposals could impact negatively on the rights and freedoms set down in the Sino-British Joint Declaration," they said.

They also pinpointed fears about the bill's effect on their citizens in the region and on business confidence in Hong Kong.

But Carrie Lam, Hong Kong's chief executive, has argued the law would close a loophole and ensure fugitives face justice.

A coalition of pro-democracy groups will hold a second large-scale protest against the bill next week, after Ms Lam said she hoped it would pass before July.